During that brief gap between VS 2015 RTM release and Windows 10 SDK release, the release version of VS 2015 will not work with the pre-release versions of the Windows 10 SDK and Universal Windows app tools so you won’t be able to develop a Universal Windows Platform (UWP) app.

What to do?

You are in the group that will be affected for the nine days between releases. We recommend that you wait to install VS 2015 RTM until July 29. Until that date, continue using the VS 2015 RC that you have today.

When Windows 10 becomes available on July 29, you can install Windows 10, then VS 2015 with the Universal Windows App Development Tools. You can then continue working on your Windows 10 apps and targeting he Universal Windows Platform with no interruption.